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R E Stull

Publications and source records attributed to R E Stull.

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Brain areas involved in the catecholamine mediated regulation of electroshock seizure intensity.

Selective treatments which alter the catecholamine content of discrete areas of the brain were tested for their effect on electroshock seizure intensity in the rat. The data indicate that depletion of noradrenaline and dopamine in near ventricular areas by the intracerebroventricular administration of the benzoquinolizine, Ro 4-1284, enhances electroshock seizure intensity. The enhancement of seizure produced by systemic Ro 4-1284 was antagonized by the intracerebroventricular injection of noradrenaline or dopamine which do not appear to penetrate more than 1 mm into the brain. Further, pretreatment with systemic iproniazid and L-dopa completely antagonized the increased seizure intensity produced by intracerebroventricular Ro 4-1284 and repleted brain catecholamines in both near and far ventricular areas. Thus, the effects of both noradrenaline and dopamine in attenuating electroshock seizure intensity appear to be exerted principally through periventricular structures.

2H-Benzo(a)quinolizin-2-ol, 2-Ethyl-1,3,4,6,7,11b-

Learning theory and knowledge structures in computer-aided instruction.

The development of computer-aided instructional (CAI) systems suffers from a lack of a cohesive theory of learning--how do students acquire and store knowledge? From studies of computer systems that learn and tutor, we can infer generic activities that appear to be integral parts of the learning process, such as aggregation, clustering, characterization, and storage for later retrieval. Learning is faster and more efficient if the goal of a task is made explicit. Hints should be given with the correct timing in relation to an objective so that students can advance in their own problem-solving strategies with the prerequisites in mind. The general form of a rule should usually be taught first, followed by exceptions and special instances. We review theories of learning associated with CAI that illustrate the classification of different types of knowledge. Rule-based (if-then) knowledge forms are represented in these theories, as are declarative and causal knowledge structures. Extracting the common themes from different classifications of knowledge may help us create better CAI.

Artificial Intelligence

Application of teaching and learning principles to computer-aided instruction.

Many authors of software providing computer-aided instruction (CAI) have no background in educational theories. This paper reviews teaching theories and ways in which instructional principles can be applied to CAI. While the lecture form of teaching has often been maligned, there are techniques for enhancing lectures that can also apply to CAI. Effective communication methods, both verbal and audiovisual, are as important in computer modules as they are in face-to-face teaching. The quality of interactive questioning and the nature and timing of feedback are critical to the success of instruction by computer. Appropriate feedback can improve retention, as can the use of proper distractors in multiple-choice questions. We present steps for developing a CAI learning module based on established principles of teaching and learning, as well as proper identification of educational goals.

Computer-Assisted Instruction